SERGIO AGUERO admits he could be on borrowed time at Manchester City following the return to fitness of Gabriel Jesus.

Sergio Aguero has cast doubt over his future at Man City following Gabriel Jesus' return from injury

Despite scoring 30 goals in all competitions this season, Aguero is bracing himself to be benched after missing several chances in the Manchester derby, when Jesus impressed as a late substitute following a two-month absence with a fractured metatarsal.

That injury re-opened the first team door to Aguero, who had been dropped following Jesus' arrival in a £27million move form Palmeiras in January.

Marouane Fellaini headbutts Sergio Aguero during Manchester derby

Thu, April 27, 2017

Click through the gallery for the best snaps of Marouane Fellaini's headbutt on Sergio Aguero

Marouane Fellaini was sent off after this moment during the Manchester derby

"Of course Gabriel's a very good young player, which is why he's at City," said Aguero. "I know there will come a time when I have to step aside. Other young strikers like Gabriel will be brought in.

"When you reach a certain age the youngsters start putting pressure on you and you have to be even better.

"I'm happy he's back now and that means I'll have to be much more focused and alert when I play. If I have to start on the bench once again, I'll have to accept it. That's football, I always respect my coaches and I certainly respect Pep."

City travel to Middlesbrough tomorrow with their manager Steve Agnew giving a warning to midfielder Gaston Ramirez, who returns following his one-match ban after being sent off early on at Bournemouth last week.

"You can't stress discipline enough," said Agnew. "I came from a disciplined background and that's how I want my teams to play.

"I don't like to go back on things but I don't enjoy it when we show a lack of it. Things like that stay with me. Having said that, Gaston has been fine and is training well."